Tempering unit



July 18, 1950 J. T. MIDYETTE, JR

TEMPERING' UNIT Filed April 8, 1949 INVENTOR i m l l N4 Y E N R. O T T A Patented July 18,u 1950 TEMPERING UNIT John T. Midyette, Jr., Cumberland Court House, Va..

Application April 8, 1949, Serial N0. 86,297

This invention relates to tempering units of the general type employed in hot water supply systems to effect the mixing of cold water with hot water in such proportions as to insure against delivery of water at an excessive temperature to any service outlet with which the supply system may be equipped.

Although the tempering unit embodying the present invention may be employed in various types of hot water supply systems, it is herein illustrated in connection with a system of the type wherein a heating coil is employed in association with a typical oil burning home heating furnace. l

The primary object of the present invention is to provide a simple, inexpensive and e'lcient tempering unit which is structurally so characterized as to enable it to be produced in its entirety from standard parts which are readily obtainable on the open market and may be easily -assembled with reference to'each other in producing a complete unit, thus obviating the necessity of special tools for use in its manufacture and at the same time insuring its user against the diculty of obtaining replacement parts if and when such parts might be required.

Other objects and advantages of the invention will become apparent from the following description when taken in connection with the accompanying drawings, in which:

Fig. 1 is a schematic. view,showing generally an oil-burning furnace with which is associated a hot water supply system having incorporated therein a tempering unit embodying the present invention. 'l

Fig. 2A is a central vertical sectional view of the tempering unit and illustrating its function- .ing position in relation to the 'heating coil of Figure 1, and

Fig. 3 is a view showing the tempering unit in elevation.

Referring generally to Figure 1, the numeral Il! indicates a conventional home heating furnace, adapted to be fired, as by any standard oil burner unit I I, and from which its heating medium, such as'hot water, may be conducted to various radiators, not shown, by way of a suitable piping sys- -tem fragmentally indicated by the numeral I2.

With the furnace I0, there is associated a hot water supply system I4 by which hot water for all house-hold purposes may be delivered to such Vfaucets or other similarly controlled outlets, not

shown, as are required at various locations in the :home, such as at'the kitchen sink, .in the bath- :room and elsewherel 2 claims. (o1. '23e-i2) yfaucets or other hot water compartment of the furnace.

The system I4 includes a heating coil or unit I5 so arranged within the usual water compartment of the furnace IIJ that it is surrounded or enveloped at all times bythe water content of the furnace. The lower and upper legs I6 and Il of the heating coil pass outwardly through the side wall of the furnace and are connected, respectively, by way of T-couplings T--T' to cold water supply and hot water delivery pipes I8 and 20, the former of which is adapted to communicate with a suitable water source and the latter of which may be connected to various outlets Wherever desired. It will be understood, of course, that the cold water supply pipe I8 may be conveniently utilized, in conjunction with its associated branch line 2|, to supply water as required to the water Also, it will be understood that the cold Water supply pipe I8 may be equipped with a branch line 22 by way of which cold water may be delivered to such faucets or other similarly controlled outlets, not shown, as are required either independently of or in close association with the hot water outlets to which the hot water delivery pipe 20 may lead.

In order to insure against delivery of water at an excessive temperature to any service outlet with which the hot water supply system I4 may be equipped, there is provided a thermally controlled tempering unit 24, which is disposed inter- `mediate the cold water supply pipe I8 and the tity of cold water from the pipe I8 into the pipe 20 at its point of connection with the upper leg I1 of the heating coil I5 as to there reduce'any excessive water temperature to a predetermined range value of, say, F. to 145 F., thus obviating all possibility of the existence of any unduly yhigh temperature in the hot water as it is drawn from the system by way of any one or more of its service outlets.

As will be best understood from an inspection of Figures 2 and 3, the tempering unit 24 consists of various standard parts which readily lend themselves for use in the assemblyl constituting the present invention. In this connection, it will be noted that the body-like housing of the unit 24 comprises a pipe coupling which includes a male section 25 and a female section 2B, the central passage of the former of which is so formed as to provide a spring receptacle 21, a valve-stem passage 28, avalve chamber 30 and a valve seat 3|. The lower screw threaded end of the section 25 is adapted to receive the internally screw threaded section 26, within which is seated a pipe section or nipple 32, between the upper end of which and the lower end of the section is clamped the peripheral margin of a disk-like valve guide 34. With the guide 34, there is associated a vertically displaceable check-valve 35, the stem 36 of which passes through the central opening of said guide and is equipped at its lower end with a cup-like disk 31, on which is carried a compression spring 38 which engages said guide from beneath and serves to normally maintain said valve in its seated position.

The upper end of the male section 25 is screw threaded throughout a portion of its length so as to receive the internally screw threadedv end of a pipe nipple and is of. a reduced outside diameter throughout the remainder of its length so as to provide an annular flange 4| forming with said nipple an annular channel C, the purpose of` which will hereinafter more clearlyV appear` Within the upper .end of the annular ange 4| there is sweated, or otherwise'suitably secured, the lower end of an inverted cup-like housing v42, within -which is locatedl a Sylphon bellows 44, the lower end of which is suitably sealed, as by a closure 45, provided on its outer face with a disk-like contact-button 46. The bellows 44 is soldered, or otherwise suitably connected, at its upper end to the end wall of the housing 42 and is maintained in communication with a bulbous capillary tube 41, the lowenend of which passes through the end wall of said housing and' is there soldered or otherwise suitably connected to it. The-bellows 44 and rits associated capillary tube 41 contains a suitable expansible medium, adapted, in accordance with well known practice, to so respond to temperature changes as to cause the bellows to expand `and contract longitudinally of itself.

Within the chamber 30 there is located a control valve 5I, the stem 52 of which 'projects .upwardly through the? passage l@Zaltandzirito .the receptacle 21 where it is provided at itsV upper end with a button-like head 54, adapted to receive the downward thrust of the bellows 44"and"the upward thrust of a compression springl'55 which is disposedabout saidstem and isseated onthe bottom wall of said receptacle.

It is important, as will hereinafterappear,

`that communication bemaintained' at all times between the channel Cand the spring receptacle 21, and to this end there are provided in the annular flange 4| ka pair or more of orifices y'55, each leading directly from said; chamber .to said channel, the latter of which opens-directly into la similar channel C surrounding the cylindrical wall of the housing 42.

As will be understoodfrom V'Figure 2, when taken in connection with Figure 1,` the tempering unit 24 may be conveniently incorporated in the system I4 `byconnecting the nipple32r tothe coupling T by way of a shortl lengtlrof pipey 51 and by connecting Ithe'nipple'4l) to the coupling T', the latter connection being Isuch that 7. the bulbous capillary tube 41 lieswithin the path'of iiow of water from the leg I1 of the heating coil I5 to the hot waterdelivery'pipe 2|).

The branch line 2| leading'from the Coldwater 'supply line I8 to the water compartmentfofthe furnace I!) is equipped with a standardhand operated 'control valve 58 by'which communilcation between the'supply lineandvwater'com- .partment .may 'be conveniently 'established 'or severed.' at will. In accordance withcusual'7 practice, the cold water supply line I8 may be, and preferably is, equipped with a standard type of check valve indicated generally by the numeral 6|) and herein illustrated as located intermediate the coupling T and the point at which said supply line joins its associated branch line 2|.

Before entering upon a detail discussion of the operation of the present embodiment of the invention, it may beiw'ell togenerally mention that the Valve 5| and its associated actuating means, namely, the capillary tube 41, bellows 44, and spring 55 are so related that the valve is vfully open during such time as said tube is subjected to a temperature of, say, 145 F. or more `and. is adapted to move toward and into its closed position as such temperature drops from that value to, say 135 F.

Taking into account the foregoing description of the invention, it will be understood that as water is drawn from the heating coil I5 by way of theihot water fdeliveryz'pipe 520 suchwaterl will pass Aupwardly-about thefcapillary tube-41. .If the water. thus drawn'fromA the heating coill I5 is at a temperature-,greater than 145 F.v it will so affect the content ofathefcapillary tube41 and the bellows 44 as fto-:causeithe latter to expand longitudinally of itself. Such :expansion of the bellows-44 Iwill cause the valve stem1-52 to-so move downwardly' against the actionof its associated *comprcssionfsprin-gafas tonopcn the valve 5|, thus permitting l.cold water to, pass upwardly from the supply.y line 'I6-through the tempering `unit 2li-.by way-of' the 'check valve-35passage 28, spring receptacle 21, orifices 56, -channels lC-C, and thenceon into the couplingT where it comingles with the'hot'v-wateras 'it 4passes fromithe legI1 into-.,saidfcoupling. Mixing of the cold water` with the hot water. in the manner just described. lowers ythe' temperature ofthe: hot V-watersas itis supplied tothe hot water delivery pipe 2U to a non-scalding Valueof.145'-F. As the hot water is further temperedv or lowered in temperature, i the Abellows 244 Acorrespondingly contracts llengthwise of itselfand thus permits the valve 5I to'moveftowardsits lclosed position under the actionof' the :springz55- The valve`-5| assumes its fully closed position at such'time as' thewaterl in t'hewicinity of the capillary tube 41 reachesa temperature of 135 F.. and vis maintained in such position-so: longas the temperatureofl thatwater does-not'exceed 135 F. However, when the' :temperature of the waterfin the vicinity :off thefcapi'llary; tube. dlfagain rises above 135 F., the valv'ef5 I'is openedunder the expanding action of the bellows 44 and to ancextent rangingfrom barelyopen ytov fully 'open depending upon fthe 1Aextent I Ito which4 the temperature of the water `in the vicinitytof'the capillary tube is raised, it being remembered thatfully open position lo'f the: valve is attained when'such' temperature reaches a value of 145 F. andis'maintained inthat position iuntilv the' ambient tem- .'peratureof the capillary-tube is lowered to effect aclosing -movementof the valve as and for the .1 purpose previouslydescribed.

Whenthehotlwater'supply-system I4 is inv'a -staticpr'balanced condition, as when all `out- .lets'ofthe :delivery pipe'2 are closed, the check- "va'1ve35fis fmaintained closed by 'its associated spring 58,1thus'bbviating the .possibilityv of any thermo-syphonv eifectfwith' 'respect to they water "content of` the' circuit whichincludes the temperfing. unit/24; aridtheheatingcoilf I5 together vwith its'f associated i' flegs I6 aand rI1. i However, @when the valve 5| is open and water 'isabeing drawn 5 from the hot water delivery pipe 2|) by way of any one of its service outlets, the check valve 35 is free to move to its open position to permit the passage of water from the cold water supply pipe I8 through the tempering unit 24 and on into the coupling T' where it, upon reaching the vicinity of the capillary tube 41, comingles with water being delivered to that vicinity from the heating coil I5.

Although only one form of the invention is herein shown and described it will be understood that various changes may be resorted to without departing from the spirit of the invention, as for example, the coupling T' may be of the screw threaded type instead of the sweated type herein illustrated, and in that event the upper end of the male section 25 could be screw threadedly connected directly to the lower arm of such substitute coupling, thus eliminating from the assembly the pipe nipple 40 which in the present instance serves to connect said male section to the T-coupling herein illustrated.

What is claimed is:

1. For use in a hot water supply system of the type including a heating unit having lower and upper legs connected respectively to cold water supply and hot water delivery pipes, a tempering unit adapted to be connected to said pipes in shunt relation to said heating unit and comprising a body-like housing in the form of a pipe coupling consisting of a male section and a female section connected to each other, the male section having a central passage and being provided with a tubular extension forming a spring receptacle and having a diametrically reduced end portion provided With an oriiice leading outwardly from said receptacle, a pipe nipple connected to said tubular extension and forming with said end portion an annular channel communicating with said orii'lce, a T-coupling having three armsone connected to said pipe nipple and its others being adapted for connection, respectively, with said upper leg and said hot water delivery pipe, a control valve including a stem located, in part, within said central passage and, in part, within said spring receptacle, a spring located within said receptacle and acting on said stern to move said valve from its open position to its closed position, a Sylphon bellows disposed in alignment with said stem and containing an expansible medium, a cup-like housing connected to said reduced end portion of said tubular extension and forming with said pipe nipple an annular upper channel communicating with said spring receptacle by way of said lower annular channel and said orifice, a capillary tube communicating with said bellows and containing an expansible medium, said capillary tube being located in the path of communication afforded between said hot water delivery pipe and said heating unit by way of said T-coupling, whereby its contained expansible medium in association with that of said bellows will cause said bellows to expand lengthwise of itself to effect opening movement of said valve against the opposing action of said spring as the ambient temperature in the vicinity of said capillary tube rises above a predetermined value, said opposing action of said spring being utilized to effect closing movement of said valve incident to a drop in said ambient temperature to a value below said predetermined value,

2. For use in a hot water supply system of the type including a heating unit having lower and upper legs connected respectively to cold water supply and hot water delivery pipes, a tempering unit adapted to be connected to said pipes in shunt relation to said heating unit and comprising a body-like housing including a pipe coupling consisting of a male section and a female section connected to each other, the male section having a vcentral passage and a spring receptacle communicating with each other and being provided with an oriiice leading outwardly from said receptacle, a T-coupling connected to said male section for communication with said spring receptacle by way of said orifice and adapted for connection with said upper leg and with said hot water delivery pipe, a central valve including a stern located, in part, within said central passage and, in part, within said spring receptacle, a spring located within said receptacle and acting on said stem tc move said valve from its open position to its closed position, a Sylphon bellows disposed in alignment with and acting on said stem to move said valve from its closed position to its open position, a cup-like housing connected to said male section in a surrounding relation to said bellows, a capillary tube connected to said cup-like housing and containing an expansible medium, said capillary tube being located in the path of communication aiorded between said hot water delivery pipe and said heating unit by way of said T-coupling, whereby its contained expansible medium will cause said bellows to so move as to eiiect opening movement of said valve against the opposing action of said spring as the ambient temperature in the vicinity of said capillary tube rises above a predetermined value, said opposing action of said spring being utilized to effect closing movement of said valve incident to a drop in said ambient temperature to a value below said predetermined value.

JOHN T. M IDYETTE, JR.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,927,036 Johnson i- Sept. 19, 1933 2,095,357 Dube Oct. 12, 1937 2,326,096 Dillman Aug. 3, 1943 

